How to spawn new particles where particles collide? (Nuclear Fusion Reaction)

[carveid4]

Hi.  new to tyflow and glad to be here.

I am trying to make a fusion reaction animation, like what is happening in the sun. Two fast-moving heavy hydron atoms colliding with each other and form a helium atom and a neutron.


Here is what I have done so far for the moving particles effect:

The idea is to zoom into the sun and sees the reaction. When time slows down we see how the particle collisions in slow motion.

Here I have a simplified scene to test the collision and the spawn. Each ball is a Hydrogen atom.



I have added a PhysX shape to let the particles collide with themselves and a PhysX Collision to let them bounce inside the box. Min friction and Max restitution to let them bounce forever.

However how to make two new particles coming out of two colliding parent particles? Ideally, the parents will die and there will be two new separate new particles as a helium and a neutron.

2 red balls -> collide -> one green ball + one yellow ball

How do I accomplish this? 

Many thanks!

[tyFlow]

Interesting...firstly I'd suggest scrapping PhysX as your sim driver here. It's probably going to be really slow for something like this and way overkill (you probably don't need all the accuracy it will give you).

I'd suggest using a Property Test to measure the neighbor count of particles within a given radius. More than 1 particle within the radius means the particle is colliding with another. Send particles out which pass the test to another event where they spawn children (and delete themselves, if you wish), and then send those children back to the event with the Property Test so the cycle continues.

[carveid4]

Hi Tyson! Thanks for the reply.

I just noticed some broken gifs and I have updated the post.

I couldn't figure out how the test value and neighbor radius in the property test work, and what is the logic behind the values. If you don't mind, what are the proper settings in the rollout?

The test particle's radius in my scene is 5cm

On the other hand, I kept the event using PhysX, and it turn out to be working very well:



But the final result if I increase the particle number maybe it will get slow, so the property test maybe better